dbonsfield



, Y, l GRINDING APPARATUS. i l A No. 292,290. Patented JAA. 22,1884.

UNITED STATES PATENT t OFFICE.

JOSEPH s. pRONsEiELD, OE OLDHAM, COUNTY OE LAnoAsrEE, ENGLAND.

GRINDING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 292,290, dated January 22, 1884.

l Application filed September 18. 1F83. (No model.) Patented in lngland'June 22, 13k-3, No. 3 ICB.

1'0 all ufl/1,0772, t may concern:

Be it known that I, JOSEPH STANDRING DEONsFIELD, a subject of the Queen of Great Brit-ain and Ireland, and residing at Oldham, county of Lancaster, England, have invented certain Improvements in Grinding Apparatus Having Traversing Grinders, (for which I have Obtained a patent in Great Britain, No. 3,108, June 22, 1883,) of which the following is a specication.

My invention relates to the apparatus employed in the grinding of carding-cylinders and cards ordinarily known as the Horsfall7 or Hardy77 roller. In the said apparatus a short cylindrical grinder is traversed to and fro upon a hollow shaft by means of an internal screw, which is cut with both rightl and left hand threads or grooves crossing each other. Previously to my invention only one grinder has been used in each apparatus. I mount two or more grinders upon a single hollow shaft, and I cut the screw with a corf responding number of sets of screw-threads. In the ordinary apparatus the fork which 'engages with the thread of the screw and acts as a nut cannot be removed without taking the apparatus to pieces by unscrewing one of the ends of the hollow shaft, and when the parts are put together again the shaft seldom runs quite true. I so construct the grinder as that thesaid fork can be readily removed through the slot in the shaft .without unscrewing the ends of the shaft.

In the accompanying drawings, Figure 1 isl a longitudinal View, partly in section, of the complete apparatus. Fig. 2 is a cross-section on the line A on a larger scale, and Fig. 3 is a longitudinal section. Figs. 4 and 5 are enlarged views of the fork and its holder. Fig.

l6 is a sectional detail view.'

` journals are prepared to screw into the ends of the shaft. In the ordinary apparatus the shaft a is only provided with the journal b, the other end of the shaft being closed with an annular disk, through which the inner shaft, c, projects and forms the other trunnion; butl I have reduced the shaft c in diameter, and

added the trunnion b, as shown in the sectional view, Fig. 6, through which the shaft passes, so that the shaft c has a long bearing in the trunnion instead of a short bearing in the disk, as in the old arrangement. 'Ihe shaft c extends from one end of the hollow shaft to the other, and is cut with right and left hand `threads d, which cross each other, as is usual.

Upon the hollow shaft are mounted two grinders, e e. The screw-shaft c is turned with two distinct sets of screw-threads, one set not running into another.

In Fig. 3, his the curved shunting-groove vwhich ends one set of threads, and t' is the shunting-groove which begins the other set,

these shunting-grooves guiding the fork from the right-hand to the left-hand threads, or,

vice versa, as is usual. Y Each grinder is traverscd by its Own set lof threads, and both move simultaneously. VVhen one grinder-say the grinder e'-is at one end of the hollow shaft, as in Fig. 1,' the grinder e will be at or aboutthe center. The rotation of the screwshaft will move both grinders toward the right hand, the grinder c moving from the left-hand end toward the center, and the other moving from the center toward the righthand end. NVhen the grinder e has reached the center, the grooveh will'shunt the forksay, for example, from the right-hand threads into the left-hand threads-the fork of the grinder e being shunted at the same time by means of a shouting-groove at theend of the screw-shaft-,and both grinders will move toward the left'hand..

The action is similar to that of the ordinary Horsfall or Hardy grinder, with the exception that the screw-.shaft of the latter has Vno shunting-grooves in the center, and has only one grinder, which traverses from end to end of the shaft, the fork being shunted by shnntinggrooves at each end of the shaft. vBy using two grinders instead of one, I can effect the grinding more quickly, as each grinder has only to grind one-half of the width of the cylinder from one edge to the center, the other grindingfrom the center to the other edge, so thatthe work can be done in about half the time usually required. The pulleys e e are covered with emery, as is usual; but I prefer to mold the emerycoating into the grooved IOO form represented in the drawings. in accordance with my English patent, dated December' 27, 1880, numbered 5,442. Each grinder consists of a metal pulley, e, which fits upon a turned block, f, and is secured thereto. The block f is formed with a turned ange, which fits against an internal flange on the pulley c, and bolts g, passing through both flanges, secure the parts together. A projection is formed on the blockf, and this projection is bored to receive a turned fork-holder, k, which is secured in place by means of a set-screw, m, or by other suitable lncans. This fork-holder is bored to receive the shank Z of the fork7 which is formed with a crutch-head, Z, which enters the grooves .of the screw and acts as a nut, whereby the grinder is moved to and fro, as is usual. Previously to my invention the shank Z has been fitted into a hole bored in the block f, which has been formed in one piece with the part e. The fork-holder is formed with a downward projection, k,whieh is placed at the sides oris otherwise fitted to slide in a slot which is formed in the hollow shaft and runs nearly from end, as in the ordinary apparatus. This projection acts as a key, whereby the grinder is caused to revolve with the shaft and also supports the fork by bringing the bearing for the shank Z close up to the erutclrliead. \Vhen the fork has become much worn, so that it is desirable to replace it with a new one, or to remove it for other reasons, the pulley e is removed by removing the bolts and drawing the pulley of the block j". The set-screw m is then slackened and the forkholder k is drawn outward until the erutchhead Z clears the screw-grooves. The shank Z is then turned until the crutch-head is in line with the slot in the hollow shaft, so that it can pass through the slot. The fork-holder k is then withdrawn, bringing with it the fork.

To permit the turning of the crutch -head into line with the slot,I make the hollow shaft larger than usual, so that there is sufficient room above the screw-shaft for the crutchhead to turn afterit has left the screw-groove. The diameter of the fork-holder must be greater than the length of the crutch-head, so that the latter will pass through the hole in which the fork-holder is fitted. The shaft might be provided with three or more grinders, the screw-shaft being cut with a corresponding number of distinct sets of screw-threads. lt' the screw-shaft were cut for three grinders, one set of screw-threads would be cut to move a grinder from one end to about one-third of the length of the shaft from the end, and to return the grinder to the end. The next set would be cut to Work a grinder to and fr0 011 the middle part ofthe shaft through about onethird of its length. The third grinder would work to and fro on the other third part ofthe shaft. In practice two grinders will usually be sufficient.

The method of mounting the fork for convenience of removal is applicable when only one grinder is mounted on the hollow shaft.

I claim as my inventionq l. In a card-grinding device7 the combination of a hollow shaft and a screw-shaft having two separate sets of serewthreads, with shunting-grooves near the center and'near the opposite ends, and two grinders each having a fork adapted to ltraverse one of said sets of screw-threads, all substantially as set forth.

2. In a card-grinding device, the combination of two or more grinders and forks there for with a rotating serew-shaft, having a corresponding number of sets of right and left "hand screw-threads, and shunting-grooves at the ends el' each set, substantially as deseibed. 3. The combination of the screw-shaft and vblock f with the fork-holder k, adapted to an opening in said block large enough for the withdrawal ot' the fork, the latter having its shank adapted to swivel in the said holder, substantially as specified.

In testimony whereof I have signed my name to this specification in the presence oftwo subseribing witnesses.

J. S. DRONSFIELI). ll'vitliesses:

EDWARD K. DU'r'rox, ARTHUR LEDGER. 

